Method and tool for securing wire screw-threads to wooden members



. July 28, 1931. x w. HEY NER ET AL 1,816,232

E SCREW THREADS 1'0 WOODE EMBERS July 28, 1.931. w. HEYNER ET AL METHODAND TOOL FOR SECURING WIRE SCREW THREAISS TO WOODEN MEMBERS Filed Nov.23, 1927 2 Sheets-Sheet 2 the helix overlap each other, since the upperPatented July 28, 1931 UNITED'S'TATESY PATENT'FOFFICIE- WILLI HEYNER, OFBERLIN, .AND HERMANN HENKEL, OF NEUKOLLN, NEAR: BEBIIIN,

- L GERMANY METHOD AND TOOL non SECURING WIRE SCREW-THREADS To woonmvMEMBERS Application filed November 23, 1927, Serial No. 235,234, and inGermany November 26, 1926.

Our invention relates generally to immetallic objects or parts, or inother words to proved means for joining together wooden solve theproblem of providing metallic articles or members with the aid of wirethreads in and on wooden objects or members helices, and moreparticularly to the manusimilar to usual threads of metallic objects.facture of metallic screws and threads in- \Vith this aim in view weemploy helical connecton with wooden members to be springs or. wirehelices which in themselves joined together. are well known, for use asexternal threads We are aware of the fact that wire helices and asinternal threads, and we attach the I or helical springs have beensuggested heresaid helical springs to the wooden objects by tofore forsimilar purposes. Thus conical firmly connecting the ends thereof withthe wire helices are used for fixing the tapering latter, as will beexplained more in detail end of a handle to a broom head or the like;with reference to the accompanying drawbut experience shows that woodenhandles, ings forming a part of this specification and plugs, or pegscannot be fixed in a reliable wherein the particular construction andmanner to a broom'or the like by means of a shape of the helical springsor wire helices conical wire helix. Now as far as our knowland the toolsfor the application and fixation edge goes cylindrical wire heliceshaving a thereof in the wooden objects or bodies are close narrow pitch,have also been suggested clearly illustrated. heretofore for fixing ahandle to a head or Before proceeding to describe the constructhe likeby inserting the wire helix into a bore tion thereof which we haveselected as best n or hole of adequate diameter and subsequentembodyingour invention, however, we dely inserting the properly pointed handleinto sire to have it understood that said construethe wirehelix byturning movements. But as tion is not the only embodiment of which ourthe pointed end of the handle gradually en invention is capable, that awide range of gages in the bore or hole, the wire helix will equivalentsmay be employed for certain parts follow and turn-together with thehandle unwhich we haveillustrated and will hereintil it reaches thebottom face of the hole after describe, and that the phraseology whichIn case of holes of a comparatively small we have adopted is for thepurpose of descripdiameter the helix must obviously be made of tion andnot of limitation except where the correspondingly thin Wire, whence itfollows sense absolutely requires it. that the lower most turns orconvolutions of In the drawings Fig. 1 is an elevational view of a wirehelix end of the wire helix is not fixed to the as employed, accordingtoour invention, for handle and the lower end thereof cannot internalthreads; Fig. 2 is an end viewtherecatch hold of the handle end becausethe latof; Fig. 3 is an elevational view of the tool ter is pointed andnecessarily must be pointed. employed for fixing one end of the Wirehelix Likewise such wire helix cannot be used for shown in Figs. 1 and2, in the cylindrical bore fixing or interconnecting plugs for the reaor hole of a wooden object or member; Fig. 4 son that the windingsorconvolutions of the is an end view thereof; Fig. 5 is a sectional helixwill move towards the front face of the view taken on the line 55 ofFig. 4; Fig. 6 plug when the faces are to be gathered or is a plan Viewof a tool employed for conscrewedup. In general all of the knowntract,ing and ;ernbedding the several turns of screws of the kind-may beadapted for use in the'helix in the wall'ofthebore-ofthe wooden bottomedholes, but they cannot serve for a member; Fig. 7 is an end viewthereof; Figr-8- regular screw connection in wooden members is a viewsimilar to Fig. 1 of a wire helix emfor want of any fixed seat orabutment. ployed, according to our invention, for ex- The object of ourinvention is to provide ternal threads adapted to co-operate with or anew method of and means for joining engage in the internal threads ofthe helix wooden objects or members in a manner simishown in Fig. 1;Fig. 9 is an end view therelar to the usual interconnection of threadedof; Fig. 10 is a front view of a tool employed L parts.

for fixing one end of the wire helix shown in Fig. 8 to the woodenmember such as a plug or peg; Fig. 11 is a plan view thereof; Fig. 12 isa side view thereof taken in the direction of thearrow of Fig. 11; Fig.13 is a sectional view on the line 13-l3 of Fig. 11; Fig. 14 is a sideview of a tool for contracting and embedding the wire helix shown inFig. 8 in the said plug and for fixing the other end thereof to thelatter; Fig. 15 is a plan View thereof; and Fig. 16 is a sectional viewof the'inner parts thereof.

The same reference symbols are used in the different figures to denotecorresponding As shown in Figs. 1', 2, 8, and 9 we use a helically woundcoil or helix made of wire of suitable preferably square cross-section.In case of a wire helix to be inserted as a lining into the bore or holeof a wooden member in order to constitute an internal thread, the wireis wound in close intercontacting turns to form a helix 1, as shown inFig. 1, of cylindrical shape and uniform size corresponding to the sizeof the said bore or hole and the size of the counter,-helix to besubsequently united therewith. The two ends 2 and 8 of the pro perlycoiled wire are bent inwards and outwards to form angles with pointedextremities extending substantially radially towards the periphery ofthe structure, as will be readily understood on inspection of Fig. 2,for purposes as hereinafter explained.

The wire helix 1 is inserted into the bore of the wooden member and oneextremity thereof, for instance 2, is then forced into the wall of thebore by means of the tool illustrated in Figs. 3 to 5. The toolcomprises two cylindrical parts 8 and .9 each provided with a handle 6and 7, respectively, and the one mounted in the other one so as to becapable of rotation therein; The outer part 8 is provided, at its oneend, with a stepped projection 10, and the inner part 9 is equipped witha laterally grooved pressure lug 11 and a pressure roller 12. Inoperation the projection 10 is inserted into the accessible front end ofthe wire helix 1 which had been previously placed in the bore of thewooden member, and as the projection 10 is eccentrically displaced withrelation to the cylindrical hole of the part 8 in which the part 9 isinserted, for the amount of twice the depth of the thread, the pressureroller 12 the periphery of which coincides with that of the '"inner part9 of thet-ool, will act upon the hooked end 2 of thewire helix and willforce the same into the wood of the bore of the member, when the handle7 is mzfiiually rotated in the direction of the arrow in Fig. 4. The end2 of the wire helix is bent back in this way and returned to circular orhelical alinement'with the turns of the helix while the pointedextremity thereof is embeddedin the wood in order to secure the wirehelix in its place.

The step 13 of the projection 10 is a sup-' plementary meansco-operating with the operative end of the part 9 of the tool to exactlyfit in the bore of the wooden member or, in other words, to supplementthe operative end of the tool to obtain substantially the same diameteras that of the bore, so that the coil or helix will be constrained toen1- bed itself into the walls of the bore or hole in which it is to beinserted, for a desirable amount of say 2 mm. in case of a helix made ofa wire of a square crosssection of 4 mm. taken on the diagonal.

Upon having fixed the front or outer end of the wire helix in the mannerdescribed the tool shown in Figs. 6 and 7 is to be applied for finishingpurposes. This tool is, generally speaking, similar to'a screw-tap, asregards form and manipulation. The operative end of the tool isprovidedwith a main roller 14 and a set of symmetrically arranged pressurerollers 15, all of the said rollers being properly mounted for rotationin the end face of the tool, the main roller 1a serving to hold andguide the turns of the wire so that they will be properly assembled andprevented from displacement and come in alining contact with theperipheral grooves of the pressure rollers 15 shaped and arranged toform a continuation of the thread'provided on the periphery of theoperative end of the tool, and partially indicated in Fig. 6 bydash-and-dot lines. The main roller 14 is located in the diameter of thebody or core of the thread K, see Fig. 1, of the helix, and the pressurerollers are mounted in the tool on pins so that their peripheral grooveswill coincide with the outermost thread of the tool.

Regarding the size and form of the pressure rollers 15 they are sodimensioned and shaped that when the tool is inserted into the hole orbore of the wooden member lined with the wire helix, and caused torotate therein, the latter will be pressed into the walls of the hole.thread by thread, to the full amountof the depth of the thread. To

this end the tool is formed with a square head so as to afford a goodpurchase for a wrench or other toolfor manipulating the same. As thetool proceeds to thus embed the main or guiding roll 14 will, at the endof the rotating operation, engage the bent portion 3 and bend the sameback into the circular form so that the pointed extremity will bepressed into the wood for the anchoring purpose. and subsequentlytherollers 15 will act to finish the work by fully embedding the portion3 and the pointed extremity thereof into the wood so that the wholelength of the Wire of the helix will lie evenly and snugly embeddedinthe wood and with the wire' helix into the walls of the hole, first itsextremities firmly secured therein so as to form an accurately threadedlining for the reception of a co-operating screw.

single turns or windings close by each other and of an internal diametercorresponding to the diameter of the. plug to be connected therewith.The two ends 17 and 18 of thecoiled wire are bent outwards and inwardsand have pointed extremities.

A wire helix 16 constructed in the described manner is attached to theplug and inserted into the hole-20 ofthe tool illustrated in Figs. 10.to'l3. The hole or opening 20 is provided with a recess 19 for the recetion of the wire end 17, and the tool serves or the operation of fixingthe wire end 17 to the plug.

To this end the tool is provided with a handle 21 and a pressure slide22 mounted on a pin 24 integral with and eccentrically projecting from arotatable bolt 23 so as to be capable of or adapted for movementstowards and away from the groove or recess 19,

a handle 25 being firmly connected withjthe bolt 23 for actuationthereof. The plug with the wire helix thereon being inserted into theopening 20 of the tool, the former is turned for a quarter of arevolution in the direction of the arrow shown in Fig. 11, whereby thepointed end or hook 17 will be placed below or in front of the pressureslide 22, whereupon the handle 25 is to be turned in the direction ofthe arrow shown in Fig. 11 until the same engages the handle 21. Themovement of the handle 25 results in a corresponding movement of thebolt 23 and of the pin 24 integral therewith. As the 'pin 24'permanently engages in a slot of the pressure slide 22, the latter willbe moved, upon the rotation of the handle 25, vertically downwards, inFig; 11, that is, towards the opening 20. The lower or inner end face ofthe slide 22 is shaped to coniorm to the radius of the wire helix 16 andrecessed according to the profile of the wirefor the latter to snuglyfit therein so that the pointed end 17 will be prevented .fromaccidental displacement.

" When the benten'd or hook 17 of the wire helix has been properly fixedto the wooden plug by means of the toolshown in Figs. 10 to 13, the nextstep of the new method resides in the application of the toolillfistrated in Figs. 14 to 16 and provided with the arms or handles formanipulation'in themanner of a screw-stock. The inner member or head 28of the toolis slotted or split and provided with' internafthreads andadapted tabs placed in the outer member or holder 29. The 3 inner member28 is provided with a main or guiding roller 30 and a set ofsymmetrically located pressure rollers 31, the arrangement of the saidrollers being, from a eneral aspect, "somewhat similar to the r01 erarrangement hereinbefore described with reference to Fig. 7. Accordinglythe rollers are peripherally grooved and the grooves of'thc pressurerollers 31 corres mud to the internal thread of the member 2 As regardsthe function of the several rollers the same is substantially similar tothat of the rollers shown in Fig. 7 The tool is appliml to the plug withthe wire helix 16-, attached thereto as described with reference toFigs. 10 to 13, by placing the same on the helix 16 and revolv ing thesame in the manner of a. screw-stock by means of the'handles 26 and 27,until the rollers 30 and 31, with the .guiding roller 30 ahead, havecompressed the wire helix and embedded the same into the wood to thedepth of the thread and with the pointed end- 18 firmly secured in thewood, so that the wire helix will form a regular, rigid metallic threadon the plug of a somewhat smaller diameter than that of thehelix in itsoriginal condition.

It goes without saying that instead of wood any other appropriatematerial may be used forpur )OSGS aimed at by the present invention; tany rate. the invention provides most suitable -means for joiningtogether separate members of. wood or any other appropriate material inthe reliable manner of a metallic screw connection, and it is aparticular advantage that by the use of a system of rollers theoperation of compressing, rlgldlfying and fixing the wire helices can be(turned out without requiring any expenditure of excessive power or askilled hand.

The thread or helix is seated or embedded inthe wood or the like sofirmly that, as experiments and tests have shown, excessive strains maycause the wood to break but the metallic threads thereon cannot bedisplaced thereby.

In this regard, therefore, a metallic connection according to thepresent invention is by far superior to any wooden screw connection andhighly practical from both the, standpoint of the manufacturer and thestandpoint of the user, since the same may be manufactured at acomparatively low cost so as to be less-expensive than wooden screwshitherto employed. Evidently the invention is a new departure'in manybranches of industry particularly in those where wooden articles aremanufactured or wooden parts are to be interconnectedi What we claim is1 a 1. A method for securing screwthreads of metallic wire'helicallywound side by side applying set eccentrically rolling into the wood andforce sure on the threads in a direction approximately radial to theaxis of the wire helix by rolling to embed the wire into the wood; andsecuring one tapered end of the wire into the' wood.

2. A method for securing screwthreads of metallic wire helically woundside by side and having tapered ends to wooden members or the like,which comprises in securing one end of the wire into the wooden member;applying pressure on the threads in a direction approximately radial tothe axis of the wire helix by rolling to embed the wire into the wood;and securing the other tapered end of the wire into the wood. v

3. A method for securing screw'threads of metallic wire having a squarecross-section and helically wound side by side on one edge and havingtapered ends, which comprises in pressure on the threads in a directionapproximately radial to the axis of the wire helix and diagonal to thesquare of the wire by rolling to embed the wire into the wood to thedepth of one-halfthe length of the diagonal; and securing one taperedend of the wire into the Wood.

4. A tool for securing a metallic wire helix to a wooden member or thelike, comprising a member having a plurality rollers in an end facethereof, said rollers being rotatably mounted and grooved to contactwith the helix to embed it by rolling into the wood and force the endthereof securely into the wood.

of pressure.

guide roller set eccentrically to the helix constituting the geometricallocus of the centers of the pressure rollers to guide the -wire to thefirst of the pressure rollers.

8. A tool for securing a metallic wire helix to a wooden member of thelike, comprising a member having in its end face a plurality of pressurerollers arranged on a helix of a pitch equal to that of the Wire helix,said rollers being rotatably mounted and grooved to contact with.thewire helix to embed it by rolling into the wood and force the endthereof securely into the wood; and a guide roller having a largerdiameter than the pressure rollers and being set eccentrically to thehelix constituting the geometrical locus of the center of the pressurerollers to guide the wire to the first of the pressure rollers.

In testimony whereof we aflix our signatures.

WILLI HEYNER. HERMANN HENKEL.

5. A tool for securing a metallic wire helix to a wooden member or thelike, comprising a member having in its end face a plurality of pressurerollers arranged on a helix of a pitch equal to that of the wire helix,said rollers being rotatably mounted and grooved to contact with thewirehelix to imbed it by rolling into the wood and force the end thereofsecurely into the wood.

6. A tool for securing a metallic wire helix to a wooden member or thelike, comprising a member having in its end face a plurality of pressurerollers arranged on a helix of a pitch equal to that of the wire helix,said rollers being rotatably mounted and grooved to contact with thewirehelix to embed it by rolling into the wood and force the end thereof socurely into'the wood; and a guiding'device pressure rollers arranged ona helix of a to the helix constituting the geometrical locus of thecenters of the presa plurality of pitch equal to that of the wire helix,said rollers being rotatably mounted and grooved to contact with thewire helix to embed it by the end thereof securely into the wood; and agrooved

